Sulfuric acid attack of mortars containing blended cements with sugarcane bagasse ash and limestone filler

Ataque por ácido sulfúrico de argamassas contendo cimentos compostos com cinza de bagaço de cana-de-açúcar e fíler calcário

Abstract

The present study evaluated the durability of mortars containing blended cements with sugarcane bagasse ash and limestone filler under sulfuric acid attack. Mortar packing density was predicted using the Compressible Packing Model, and tests for compressive strength, water absorption, and capillarity were conducted alongside microstructural analysis by scanning electron microscopy. Although the mortars had similar packing density values, both supplementary cementitious materials densified the microstructure and reduced gypsum formation after acid attack. While sugarcane bagasse ash improved mechanical performance due to synergistic physical and chemical effects, its pozzolanic activity did not enhance the mortar acid resistance. However, bagasse ash-blended mortars showed notable reductions in water absorption and sorptivity post-acid attack compared to other mixes.

Keywords
Blended Portland cement; Sugarcane bagasse ash; Limestone filler; Acid attack; Durability; Sorptivity